Problem: $ { \left[\begin{array}{rr}{3} & {-1} \\ {0} & {3} \\ {4} & {2}\end{array}\right]+\left[\begin{array}{rr}{-2} & {-1} \\ {-1} & {-2} \\ {1} & {0}\end{array}\right] = {?} } $
Answer: To find the sum of two matrices, add the corresponding items between each matrix. ${\left[\begin{array}{rr}{3}+{-2} & {-1}+{-1} \\ {0}+{-1} & {3}+{-2} \\ {4}+{1} & {2}+{0}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rr}{1} & {-2} \\ {-1} & {1} \\ {5} & {2}\end{array}\right]}$